This invention relates to a container of plastics material with a lid having a skirt extending downwardly around the upper edge portion of the container wall, the lower edge portion of the skirt being covered by a protecting member connected with the outer side of the container and having a flange located outside the skirt of the lid and substantially parallel thereto.
Such containers are known from the U.K patent specification No. 1,489,515. These known plastics containers distinguish themselves by providing an efficient safety against unintentional disengagement of the lid from the container by forces tending to press the skirt of the lid outwardly and upwardly, such as may e.g. occur if two filled containers, not having a protecting member as described, happen to be placed in such a manner that the lower edge of the skirt of the lid of one container rests on the upper edge of the lid of the other container.
However, these known containers have the drawback that they do not provide a similar safety against unintentional opening in the event of pressure created within the container. In such case the central portion of the lid will be domed upwardly whereby the lid may be disengaged from the upper edge portion of the container. This drawback is especially manifest in the case of containers having a relatively large volume, such as 1 l. or more.
A similar problem may occur when the sides of relatively large containers are pressed against one another.